Hydraulic jarring tool



April 27, 1965 J. C. MASON HYDRAULIC JARRING TOOL Filed Aug. 24. 1961 mms/Ton JAMES C. MASON ATTORNEY United States Patent iltice lflf Patented Apr. 27, 1965 The present invention relates generally to oil field drilling equipment, and more particularly to a hydraulically operated jar that may be dropped through a string of drill pipe and a drill collar to come to rest in contact with a collar-supported bit to impact against the bit and free it, the drill collar, or drill pipe from a stuck position in a bore hole.

Although a number of hydraulically operated jars have been devised and used in the past, these devices have suffered from certain operational disadvantages in that they had to be lowered into the well by a string of tubing or other means which is a time-consuming and expensive operation, or included initially as a part of the operating string that rotates the bit.

A major object of the present invention is to provide a hydraulically operated jar that may be dropped downwardly through a drill string and drill collar to contact the bit or portion of the collar and impact against the same, which when the bit, drill collar or drill string freed, is easily recovered by use of a cable-supported retrieving tool.

Another object of the invention is to supply a hydraulically operated jar that has an extremely simple mechanical structure, is quick and easy to use, can be fabricated from standard, commercially available materials, requires a minimum of maintenance attention, and can be sold or leased at a suiiiciently low ligure as to encourage the widespread use thereof.

Yet another object of the invention is to furnish a hydraulically operated jar of such rugged structure that little or no damage can be done thereto even when the jar is subjected to the most harsh and careless treatment.

A still further object of the invention is to provide a means to free a stuck bit, drill collar, or portion of driil pipe without having to resort to determination of free points, stuck points, use of a magnet detector, or attempting a back-off operation, all of which means are not only time-consuming but exceedingly expensive.

Yet another object of the invention is to provide a hydraulically operated jar that is activated by the kinetic energy of a downwardly moving liquid column in the tubular member in which the invention is disposed.

A still further object of the invention is to provide a hydraulically actuated jar through which iiuid under pressure can circulate until a predetermined velocity is attained, with the circulation being suddenly obstructed when this predetermined velocity is reached, with the kinetic energy of the moving column of liquid being utilized to impact a mandrel on an anvil forming a part of the invention when the circulation is terminated.

Yet another object of the invention is to supply a hydraulie jar that is adapted to be either removably positioned relative to a drill bit or included as a permanent part of the bit and drill pipe assembly.

These and other objects and advantages of the present invention will become apparent from the following description of a preferred form thereof, and from the accompanying drawings illustrating that form, in which:

FIGURE l is a side elevational view of the invention after it has been dropped through a string of drill pipe and a drill collar to rest on the upper end of a stuck bit;

FIGURE 2 is a combined side elevational and longitudinal cross-sectional view of the invention showing the mandrel thereof in a first raised position;

FIGURE 3 is a combined side elevational and longi tudinal cross-sectional view of the invention showing the mandrel in a second position wherein it is in contact with the bit.

FIGURE 4 is a transverse cross-sectional view of the device taken on line 4 4 of FIGURE 2;

FiGURE 5 is a partial side elevational View of the upper portion of the invention shown being engaged to be moved upwardly through the drill string; and

FIGURE 6 is a transverse cross-sectional view of the invention taken on line 6 6 of FIGURE 2.

With continuing reference to the drawing for the general arrangement of the invention, it will be seen to include a tubular shell A, the lower wall portion of which is substantially heavier and delines an anvil B. Shell A and anvil B provide a ring-shaped surface C at the junction thereof. Shell A has at least one upper port D, as may best be seen in FIGURE 4, formed therein as well as one lower elongate port E. Two oppositely disposed transverse bores F are formed in shell A, which are preferably situated below port D and above the lower extremity of port E.

ln FGURES 2 and 3 it will be seen that a cylindrical mandrel G is slidably movable in the tubular shell A. Mandrel G includes as an integral part thereof an upper tubular sleeve H that extends upwardly therefrom beyond the upper end of shell A. A transverse bore J is formed in the lower portion oi mandrel G which is slightly larger in transverse cross section than that of the two bores F. When the mandrel G is in a first position as shown in FIGURE 2, the bore J is coaxially aligned with two bores F.

rl`he bore l has two balls K disposed in opposite end portions thereof, and these balls are at all times urged outwardly in opposing directions by a compressed helical spring L situated within the contiines of bore l. The balls K are of larger diameter than that of the bores F. When the mandrel G is in the tirst position shown in FIGURE 2, it is so removably held by outer portions of the balls K which extend into the inner portions of the two bores F.

Sleeve H has at least one port M formed therein that is in transverse alignment with the port D (FIGURE 4) when the mandrel G is in the first' position shown in FIGURE 2. In FIGURE 4 the invention is shown as including two oppositely disposed iirst ports M which are transversely alignable with the two upper ports D. Sleeve H is prevented from longitudinally separating from shell A, as well as rotating relative thereto, by two transversely positioned, oppositely disposed pins N that extend inwardly from the side wall of the shell A. The inner portions of the pins N slidably engage two oppositely disposed, longitudinally extending slots O formed on the exterior surface of sleeve H. Pins N are preferably held in two transverse bores P formed in shell A by conventional locking means Q. The upper end of sleeve H has an outwardly extending ring-shaped collar R mounted thereon. A yoke S extends upwardly from collarl R and supports an upright rigid member T, which latter member terminates in an enlarged engageable portion U that can be removably engaged by an engaging member V, as may best be seen in FIGURE 5. Engaging member V is supported on the lower end of a cable W.

In a rotary drilling operation, a bit X may become stuck in a bore hole Y, as may the drill collar Z that supports the bit on the lower end thereof. The drill collar Z is in turn supported on the lower end of a drill string 1) that extends upwardly to a drill stem or Kelly 12. The drill stem is rotated by a power-driven rotary table i4 and is vertically movable relative thereto. Table 14 is supported on a floor 16 of a derrick (not shown).

The upper end of the drill stem 12 is rotatably supported in a swivel 18. Liquid in the form of drilling 3 mud is supplied under pressure from a hose 2@ to the swivel 18 by a pump (not shown), and thereafter flows downwardly therethrough to the drill stem'12. The fluid flows through drill stem l2 anddownwardly through the drill stringi@ and drill collar Z. At the lower end of drill collar Z, fluid ows therefrom into a passage 22 in the bit X that is in communication withy one or more discharge ports 24 formed in the bit. VAfter discharging fromv ports 24, fluid flows upwardly in an annuius-shaped space 26 dened between the bore hole Y and the exterior surfaces of the drillcollar Z and drill string i@ to a reservoir (not shown) at thepground surface where the iiuid is again pickedup by the suction of a pump (not shown) and recirculated through the hose'it to the swivel 18.

The jarring tool of the present invention will normally be used to free the drill bit X after the bit has progressed to a considerable depthl in the borehole Y. .When bit X VVis so disposed, a ycolumn kof liquid mud will ll the drill collar Z and drill string it), as well as'the annulus-shaped space 26.V When itV is necessary to use therinvention to free the drill bitX, the tool is simply inserted within the drill stem i2,rand allowed to drop downwardly therethrough into the drill string MB. The transverse Vcross Y section of themandrel G and the sleeve'H thereof is Vsubstantially less Vthan the interior cross section of the drill coliarV Z, tubing string 19, and drill stem 12. V-The l .invention continues to move downwardly through drill string It) by gravity until it comes to rest at the lower end of drill collar Z in Contact with the upper end of bit X, as shown in FIGURE 2. Due to the viscosity of thevliquidv mud standing in the drill string l@ and drill collar Z, the downward movement of theY inventionVV by the force of gravity is slowed down to the extent that the invention is not damaged when it cornes to rest yin the position shown in FIGURE 1.

After the jarring tool has been sofdisposed, the pump (not shown) isV speeded upto start discharge of liquidat a relatively high velocity through the hose 2t) into the swivel 1S and thence downwardly through the drill string to the invention.V The downwardly Vmoving liquid in drill pipe 10 enters the upper open end 21 of Y sleeve H and flows downwardly through the sleeve to discharge through the ports M and D into the space 26. As the velocity of the downwardly moving liquid increases, a back pressurey develops as the liquid tends to escape vat 'an increasing rate from the ports M and D. When this back pressure increases to a predetermined magnitude,

the inwardly directed forces on the balls K is greater than the outwardly directed forces to which the balls lare subjected by the compressed springL. The Vballs K then move inwardly to permit mandrel G to move downwardly from the rrst position shown in FIGURE 2 to the second position shown in FIGURE 3. This movement'of mandrel G takes place very rapidly after they initiation thereof, and as a result the mandrel impacts with veryV considerable force on the anvil B.

stuck position.

A helical Yspring 32 encircles the upper portion of sleeve H,Vwith the upper end: of the spring abuttingagainst the lower surface of collar R and the lower end of the spring resting on an upper end 35 of shell A. When mandrel G moves downwardly in shell A due to the back pressure Vmentioned hereinabove, the spring 32 is compressed to the positionY shown in FIGURE 3 and tends to return the mandrel and sleeve to therst position shown in FIG- URE 2.

pump (not shown) is stopped, the spring 32 expands and returns 'the mandrel G from the second positionV (FIGURE .outwardly intorthe bores ,F due to the compression of spring L to again removably support the mandrel G in the rst position. The operation described hereinabove is thereafter repeated until the impacting of mandrel G on the bit X is suflicient to loosen the bit X or drill collar ZV from the stuck position itroccupied in bore hole Y.l

p 'From the above description; of the operation of the invention and the structure thereof, it will be seen that blows of substantial magnitude can Vbe given directly to the drill bit X. The magnitude of the force imparted to the b it X is dependent on the height of the fluid column in the bore hole Y, the density of the uid, and the velocity with which the tluid is circulated when the invention as- Y sumes the position shown in FIGURE 3.

The engaging member V, as mayl best be seen'in FIG- URE S, includes an elongate heavy cylindrical tbody 34 that depends from cable Two or more laterally spaced arms 3d are pivotally supported in downwardly extending positions from the lower end of body 34. Inwardly eX- tending claws 38 are formed on the lower ends of arms 36. When the body 34 is lowered into a position adjacent the invention, the ,arms 36 first pivotV outwardly when they come into contact with an upper conical face 40 of engageable memberv U and then pivot inwardly by gravity afterV the claws 3S have `passed below the memberv U and engage same. If thercable W and thebody 34 are then moved upwardly, the upper edge surfaces of theY claws k38 `engage thelower surface 42 ofthe member U,V and the invention caribe retrieved from the bore hole Y. The

' v-surfacerof bitxX, it will be apparent that the diameter VWhen the'invention is in the first position, the liquid i owing downwardly through sleeveV H flows outwardly` therefrom into space 26 through ports M `and D. Liquid linspace 26 that has discharged through ports AM and D rechters 'the inventionrthrough the port E to tiow down-Y wardly through a passage 23 in anvil B to the passageY Y22. Liquid discharges from passage 22 into annulus- V'shaped space 26 as previouslyV mentioned, and is recirculated by the pump (not shown) through hose 2i to swivel 18. Y

When the mandrel G moves from the first position to the second position, the port E is completely obstructed, Y

and the downwardly moving column ofliquid inrdrill string It) cannot'ow through the invention .to passage 22 and thence to space 26. This interruption of tiow of the downwardlymoving liquid column is sudden, and is VYterminated in. the length of' time it takes mandrel'G to VVmove from the iirst to the second position. The downwardly moving liquid column has, a very substanof the anvil B can be such as to transfer such impact energy to aseat (not'shown) formedin the drill collar Z,

Y or other desired portion of the collar Z or drill string 10.V

Qf course, it is .desirable that thev surface which receives the impact energy be as close as possible to the part of .n the drill string assembly that is stuck, which inthe majority of cases will be the bit X, Also, if desired the inven-V tion need notbe movable relative to drill string 10 but After the mandrel has impacted against the ringa shaped surface C due to the backV pressure build-up, the

can be Vincluded as a part of the collar lZ, or other de-YV sired portion of the drill string assembly.

Although the present invention is fully capable of achieving the` objects and providing the advantages hereinberfore mentioned, it is'to be understood that it is merely illustrative of the presently preferred embodiment thereof and I do not=mean to beV limited tothe details of construction Yherein shown and described,V other than as defined inV the Vappended claims. I claim:

` 1. A jarring tool,V capable of being dropped down through a drill stringrand -a drill collarv to apositon in contact withr'a bit'suppor'ted from the lower end of saidV collar when said drill string and collar are in a bore hole filled with a fluid with said uid standing as a column in said drill pipe and collar, including: a tubular shell having an upper port, a lower port, and two oppositely disposed transverse bores; a tubular anvil supported from the lower end of said shell, with said anvil resting on said bit so as to transmit impacts thereto; a mandrel slidably movable in said shell; a sleeve extending upwardly from said mandrel beyond the upper end of said shell, said sleeve having a iirst port therein that is transversely aligned with said upper port when said sleeve and mandrel are in a iirst elevated position above said anvil; pressuresensitive holding means carried by said mandrel and in alignment with said transverse bores in said shell so as to be subjected to the pressure of said fluid in an annulus between said tool and drill collar, with said holding means maintaining said mandrel and sleeve in said first position until said holding means is subjected to greater than a predetermined downward force that is generated by pumpi ing said uid into said drill pipe and drill collar downwardly through said shell, outwardly through said upper port to develop a back pressure in said shell greater than said predetermined downward force, with said fluid as discharged from said upper port entering said annulus which uid flows from said annulus through said lower port into said shell to enter a passage formed in said bit that extends therethrough to communicate with said Huid in a second annulus-shaped space defined between said bore hole and the exterior surfaces of said drill collar and said drill pipe; means for maintaining said mandrel and sleeve in a non-rotating position in said tubular shell; and spring means for returning said mandrel and sleeve to said first position after said back pressure has forced said mandrel and sleeve downwardly from said first position to a second position where said mandrel impacts said anvil and imparts a jar to said bit.

2. A jarring tool as defined in claim l wherein said pressure-sensitive holding means are two laterally separated balls movably disposed in a second transverse bore that extends through said mandrel, a compressed helical spring disposed in said second bore that at all times tends to move said balls outwardly away from one another to seat in said bores in said shell that are smaller in transverse cross section than that of said second bore, said bores in said shell and said second bore being in coaxial alignment when said mandrel and sleeve are in said first position, and outer portions of said balls extend into said first bores to hold said mandrel and sleeve -at said first position.

3. A jarring tool as defined in claim l wherein said means for maintaining said mandrel and sleeve in said non-rotating position is at least one pin that extends inwardly from said shell, and said pin slidably engages a slot formed in said sleeve.

4. A jarring tool as defined in claim 1 wherein said shell has an outwardly projecting collar mounted on the upper end thereof and said spring means is a helical spring that encircles the portion of said sleeve disposed above said shell, said spring having the lower end thereof in abutting contact with the upper end of said shell, and the upper end of said shell bearing against said collar.

5. A jarring tool as defined in claim l which also includes engageable means mounted on the upper end portion thereof for retrieving said tool `from a bore hole by use of cable-supported engaging means.

References Cited by the Examiner UNITED STATES PATENTS 2,620,162 12/52 Pennington 175-296 2,723,106 11/55 Merten 175-296 X 2,894,724 7/59 Andrew 16S-178 2,961,048 11/60 Davis 13S-713 NORMAN YUDKOFF, Primary Examiner. CHARLES D. ANGEL, Examiner. 

1. A JARRING TOOL CAPABLE OF BEING DROPPED DOWN THROUGH A DRILL STRING AND A DRILL COLLAR TO A POSITION IN CONTACT WITH A BIT SUPPORTED FROM THE LOWER END OF SAID COLLAR WHEN SAID DRILL STRING AND COLLAR ARE IN A BORE HOLE FILLED WITH A FLUID WITH SAID FLUID STANDING AS A COLUMN IN SAID DRILL PIPE AND COLLAR, INCLUDING: A TUBULAR SHELL HAVING AN UPPER PORT, A LOWER PORT, AND TWO OPPOSITELY DISPOSED TRANSVERSE BORES; A TUBULAR ANVIL SUPPORTED FROM THE LOWER END OF SAID SHELL, WITH SAID ANVIL RESTING ON SAID BIT SO AS TO TRANSMIT IMPACTS THERETO; A MANDREL SLIDABLY MOVABLE IN SAID SHELL; A SLEEVE EXTENDING UPWARDLY FROM SAID MANDREL BEYOND THE UPPER END OF SAID SHELL, SAID SLEEVE HAVING A FIRST PORT THEREIN THAT IS TRANSVERSELY ALIGNED WITH SAID UPPER PORT WHEN SAID SLEEVE AND MANDREL ARE IN A FIRST ELEVATED POSITION ABOVE SAID ANVIL; PRESSURESENSITIVE HOLDING MEANS CARRIED BY SAID MANDREL AND IN ALIGNMENT WITH SAID TRANSVERSE BORES IN SAID SHELL SO AST TO BE SUBJECTED TO THE PRESSURE OF SAID FLUID IN AN ANNULUS BETWEEN SID TOOL AND DRILL COLLAR, WITH SAID HOLDING MEANS MANTAINING SAID MANDREL AND SLEEVE IN SAID FIRST POSITION UNTIL SAID HOLDING MEANS IS SUBJECTED TO GREATER THAN A PREDETERMINED DOWNWARD FORCE THAT IS GENERATED BY PUMPING SAID FLUID INTO SAID DRILL PIPE AND DRILL COLLAR DOWNWARDLY THROUGH SAID SHELL, OUTWARDLY THROUGH SAID UPPER PORT TO DEVELOP A BACK PRESSURE IN SAID SHELL GREATER THAN SAID PREDETERMINED DOWNWARD FORCE, WITH SAID FLUID AS DISCHARGED FROM SAID UPPER PORT ENTERING SAID ANNULUS WHICH FLUID FLOWS FROM SAID ANNULUS THROUGH SAID LOWER PORT ITO SAID SHELL TO ENTER A PASSAGE FORMED IN SAID BIT THAT EXTENDS THERETHROUGH TO COMMUNICATE WITH SAID FLUID IN A SECOND ANNULUS-SHAPED SPACE DEFINED BETWEEN SAID BORE HOLE AND THE EXTERIOR SURFACES OF SAID DRILL COLLAR AND SAID DRILL PIPE; MEANS FOR MAINTAINING SAID MANDREL AND SLEEVE IN A NON-ROTATING POSITION IN SAID TUBULAR SHELL; AND SPRING MEANS FOR RETURNING SAID MANDREL AND SLEEVE TO SAID FIRST POSITION AFTER SAID BACK PRESSURE HAS FORCED SAID MANDREL AND SLEEVE DOWNWARDLY FROM SAID FIRST POSITION TO A SECOND POSITION WHERE SAID MANDREL IMPACTS SAID ANVIL AND IMPARTS A JAR TO SAID BIT. 